code: def add_subparser(self, name, parser):
      # pylint: disable=protected-access
      description = (
          """Train the specified model on the specified dataset."""
      )
      subparser = parser.add_parser(
          name, description=description, help="Train a model"
      )
  
      subparser.add_argument(
          "param_path",
          type=unicode,
          help="path to parameter file describing the model to be trained",
      )
  
      subparser.add_argument(
          "-s",
          "--serialization-dir",
          required=True,
          type=unicode,
          help="directory in which to save the model and its logs",
      )
  
      subparser.add_argument(
          "-r",
          "--recover",
          action="store_true",
          default=False,
          help="recover training from the state in serialization_dir",
      )
  
      subparser.add_argument(
          "-o",
          "--overrides",
          type=unicode,
          default="",
          help="a JSON structure used to override the experiment configuration",
      )
  
      subparser.add_argument(
          "--file-friendly-logging",
          action="store_true",
          default=False,
          help="outputs tqdm status on separate lines and slows tqdm refresh rate",
      )
  
      subparser.set_defaults(func=train_model_from_args)
  
      return subparser
  
imports: from __future__ import with_statement
  from __future__ import absolute_import
  import argparse
  import json
  import logging
  import os
  import re
  import torch
  from allennlp.commands.evaluate import evaluate
  from allennlp.commands.subcommand import Subcommand
  from allennlp.common.checks import ConfigurationError, check_for_gpu
  from allennlp.common import Params
  from allennlp.common.util import prepare_environment, prepare_global_logging, get_frozen_and_tunable_parameter_names
  from allennlp.data import Vocabulary
  from allennlp.data.instance import Instance
  from allennlp.data.dataset_readers.dataset_reader import DatasetReader
  from allennlp.data.iterators.data_iterator import DataIterator
  from allennlp.models.archival import archive_model, CONFIG_NAME
  from allennlp.models.model import Model, _DEFAULT_WEIGHTS
  from allennlp.training.trainer import Trainer
  from io import open
label_desc: Use image node_id 1 for calling the Train obj's underlying member method code with example usage: obj.add_subparser(name, parser) and returns: subparser